Engine not running smooth -> surging

[ejfluhr@wc101.residence.gatech.edu]

Sorry if this has already been, out.  I received an error message, and
didn't think it made it.

Hi gang,

I did some work on my car this winter vacation, and now it won't run
smoothly.  It surges back and forth at highway speeds, and it won't
idle properly when warm.  It sometimes surges between 800 and 1500 rpm
when idling, other times it just stays around 1200 (but not smooth,
still minor surging).  It ran fine down in South Florida, although I
only tested it for three days.  The problem started on the trip up.

Over vacation I fixed the cooling system, replace the Champion plugs
with Bosch triple electrode, set the timing, and played with the
mixture adjustment until it idled well (only involved a small amount
of rotation).  Nothing else we did should have affected the engine.
I cannot see or hear any vacuum leaks, although the engine died when
I pulled the electrical connector off of the idle stabilizer.  Is this
normal?

Thanks for the help,
Eric